1. Field of the Invention
The present invention relates to network AV (Audio Video) network systems, and more preferably to a network AV system using a general-purpose personal computer (hereinafter simply as “PC”).
2. Description of the Related Art
Today, PCs have come into widespread use in general households and more users have come to listen to music using their PCs. Music reproducing application programs are installed in their PCs for reproducing music with the PCs. The music reproducing application program allows an AV file to be read out from the hard disk or a CD (Compact Disk), and the decoded music data is provided to the sound board mounted in the PC. The sound board converts the music data into analog audio signals for application to the speaker.
The quality of music reproduced by the PC is however considerably degraded as compared to dedicated audio equipment and not high enough to satisfy the user. Application programs other than the music reproducing application program run in the PC at the same time, and therefore alert tones or the like produced by those application programs are sometimes audible in reproduced music.
Meanwhile, network AV systems based on a client-server system have recently been provided. Typical such systems reproduce music, while others reproduce video. In the following, those for reproducing music will mainly be described by way of illustration.
According to the disclosure of PCT/JP03/06552 filed prior to the present application, a network audio system includes server machine that stores a large number of AV files and client machine connected through a LAN (Local Area Network). The client machine requests the server machine to provide a desired AV file, and the server machine distributes the requested AV file to the client machine in response. The client machine reproduces music based on the AV file distributed from the server machine.
The network audio system further includes controller equipment that monitors and controls the client machine through the server machine. The controller equipment monitors the state of the client machine and instructs the client machine to carry out desired operation in response to the operation of the user.
The network audio system can reproduce high quality music but the user must have some knowledge about LAN in order to set up the system. Audio users can often be PC users as well, but not many of them have enough knowledge about LAN to build up a home network. This is a primary reason why the network audio system is not widespread.
The PC can reproduce music based on all the AV files in the hard disk or the like, but the network audio system can reproduce music only based on AV files registered in the server machine. The AV files existing in the hard disk or the like may be registered and then reproduced, but the process of registering them is complicated.
The document on the Internet at URL: http://www.cd3o.com/index.html under the title of “cd3o Network MP3 Players” (found by searching online on Jun. 13 and 17, 2003) discloses a network MP3 player that can be connected to existing audio equipment. According to the document, digital music is transmitted by radio to the network MP3 player through a home network from a PC. In this way, the user can listen to the digital music on the PC using the existing audio equipment.